The G Plan Diet is a book published in January 2017 that promotes gut-healthy weight loss over 21 days. It reveals how an unbalanced gut can cause weight gain and other issues, and shows how nourishing the gut with certain foods can help lose weight and improve energy and mood. The diet plan gradually builds up gut health over three weeks through a menu plan and recipes. People typically lose half a stone in the 21 days and continue losing weight while feeling less hungry. The book is written by established nutritionist Amanda Hamilton and writer Hannah Ebelthite.